The field of the invention is medical imaging and particularly, methods for enabling physicians to select and display diagnostic images from image data acquired with medical imaging systems.
There are many imaging modalities used to acquire medical images suitable for diagnosing disease or injury. These include x-ray, CT, magnetic resonance imaging (MRI), ultrasound and nuclear medicine systems. These medical imaging systems are characterized by their ability to acquire large amounts of image data during a patient scan. The image data may be acquired directly as a three-dimensional (xe2x80x9c3Dxe2x80x9d) image, but in most cases the image data is acquired as a series of contiguous two-dimensional (xe2x80x9c2Dxe2x80x9d) slice images that may or may not be combined to form a 3D image.
In many cases the location of the disease or injury is well defined and the physician can prescribe a scan which acquires an appropriate amount of image data at and around the known location. For example, the region of interest in a scan of a knee, shoulder or elbow to diagnose a joint injury can be precisely defined. The acquired image data in such cases is relatively limited in scope and its display relatively straight forward. For example, 10 to 1000 2D slices may be acquired and viewed one at a time by the physician to diagnose the injury.
As imaging systems have improved in speed and image quality, their medical applications have expanded. One such application is the use of an x-ray CT system in a trauma center to help find and diagnose injuries. In such applications huge amounts of image data may be acquired (e.g. 300 to 1000 2D slices) over a large region of the patient (e.g. chest/abdomen/pelvis). As a result, the physician is faced with the formidable task of viewing all the acquired 2D slice image data to locate the region of interest where the injury has occurred and then to select the diagnostically most useful images. This procedure is time consuming and monotonous.
The present invention is a method and system for enabling large amounts of image data to be displayed such that the diagnostician can easily locate a region of interest in the field of view of the acquired image data and precisely specify a set of 2D diagnostic images that encompass the region of interest. More particularly, the acquired image data is processed to produce a 3D image data set; the 3D image data set is used to produce an index image on a display which depicts the subject of the scan in 3D throughout the field of view of the acquired image data; a pointing tool is provided to enable the diagnostician to select a region of interest in the index image; and a prescription tool is provided to enable the diagnostician to specify a set of 2D diagnostic images which depict the subject of the scan as a corresponding set of 2D slices through the region of interest. The prescription tool enables the number, size and orientation of the 2D slices to be specified by the diagnostician such that the number of diagnostic images may be limited to a reasonable number while providing maximum diagnostic information.